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Measuring Humidity

High Humidity Can Cause Serious Crawl Space Issues

Hot temperatures and humidity can cause issues in the crawl space of your home.

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With the increase in temperatures and humidity during the summer, homeowners will often find they have serious issues in their crawl spaces — if only they take the time to have them inspected.

As the hot, humid outdoor air enters a crawl space through the foundation vents and mixes with the cooler air under a home, the relative humidity of the air increases. For every 1 degree Fahrenheit temperature drop of this hot air coming into the crawl space, the relative humidity of this air increases by 2.2%. As a result, the humidity of the air under your home can actually be significantly higher than the humidity of the outdoor air.

Basement Authority of West Virginia recently inspected a home that displayed this phenomenon very well. The air outside was 82.6 degrees Fahrenheit with 65.2% relative humidity. Underneath the home, though, the air was 72.1 degrees Fahrenheit, but the relative humidity was 85%! Water was found dripping on insulation and floor joists. Insulation was falling down across large sections of the crawl space. Because of the damp conditions and wet insulation, several floor joists were soaked.

Over time, if no action is taken, the wood under this home will rot prematurely, mold and mildew will grow and the conditions under the home will cause the air quality in the home to deteriorate.

As displayed with this dew point calculator there will be serious issues if the humidity remains the same under this home. To use this calculator, simply plug in the numbers we found under this home. As you can see after running this calculator, conditions are favorable for mold to begin growing under this home in mere days, not weeks or months!

Basement Authority of West Virginia offers free, no obligation inspections of crawl spaces. We will take pictures to show you exactly what is occurring in your crawl space and use scientific instruments to not only measure relative humidity, but to also check the moisture content of the wood under your home.

What you don’t know may be making you sick (mold or mildew), rotting the wood under your home and creating comfort issues in your home. Contact us today for a free, no obligation inspection.

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